OCA: Oracle Certified Associate Java SE 8 Programmer I Study Guide

Jeanne Boyarsky, OCA/OCP, has worked as a Java developer for a bank in NYC for 12 years where she develops, mentors and conducts training. In her free time, she is a senior moderator at CodeRanch and works on the forum code base.Scott Selikoff, SCJP, has been a professional Java Enterprise developer for over 15 years. He currently operates Selikoff Solutions, LLC, which provides software consulting services to businesses in the tri-state New York City area.

• Introduction xxiAssessment Test xxxi Chapter 1 Java Building Blocks 1Understanding the Java Class Structure 2Fields and Methods 2Comments 4Classes vs. Files 5Writing a main() Method 6Understanding Package Declarations and Imports 9Wildcards 10Redundant Imports 11Naming Conflicts 12Creating a New Package 13Code Formatting on the Exam 16Creating Objects 16Constructors 17Reading and Writing Object Fields 18Instance Initializer Blocks 18Order of Initialization 19Distinguishing Between Object References and Primitives 20Primitive Types 20Reference Types 24Key Differences 25Declaring and Initializing Variables 25Declaring Multiple Variables 26Identifiers 27Understanding Default Initialization of Variables 29Local Variables 29Instance and Class Variables 30Understanding Variable Scope 31Ordering Elements in a Class 34Destroying Objects 36Garbage Collection 36finalize() 38Benefits of Java 39Summary 40Exam Essentials 41Review Questions 42  Chapter 2 Operators and Statements 51Understanding Java Operators 52Working with Binary Arithmetic Operators 53Arithmetic Operators 53Numeric Promotion 55Working with Unary Operators 57Logical Complement and Negation Operators 57Increment and Decrement Operators 58Using Additional Binary Operators 60Assignment Operators 60Compound Assignment Operators 62Relational Operators 63Logical Operators 64Equality Operators 65Understanding Java Statements 66The if-then Statement 67The if-then-else Statement 68The switch Statement 72The while Statement 76The do-while Statement 78The for Statement 80Understanding Advanced Flow Control 86Nested Loops 87Adding Optional Labels 87The break Statement 88The continue Statement 90Summary 92Exam Essentials 92Review Questions 94Chapter 3 Core Java APIs 101Creating and Manipulating Strings 102Concatenation 102Immutability 104The String Pool 105Important String Methods 105Method Chaining 110Using the StringBuilder Class 111Mutability and Chaining 112Creating a StringBuilder 113Important StringBuilder Methods 114StringBuilder vs. StringBuffer 117Understanding Equality 117Understanding Java Arrays 119Creating an Array of Primitives 119Creating an Array with Reference Variables 121Using an Array 123Sorting 124Searching 125Varargs 126Multidimensional Arrays 126Understanding an ArrayList 129Creating an ArrayList 129Using an ArrayList 130Wrapper Classes 134Autoboxing 136Converting Between array and List 136Sorting 138Working with Dates and Times 138Creating Dates and Times 138Manipulating Dates and Times 142Working with Periods 145Formatting Dates and Times 148Parsing Dates and Times 151Summary 151Exam Essentials 152Review Questions 153Chapter 4 Methods and Encapsulation 165Designing Methods 166Optional Specifiers 168Return Type 169Method Name 170Parameter List 171Optional Exception List 171Method Body 171Working with Varargs 172Applying Access Modifiers 173Private Access 173Default (Package Private) Access 175Protected Access 176Public Access 180Designing Static Methods and Fields 181Calling a Static Variable or Method 182Static vs. Instance 183Static Variables 185Static Initialization 186Static Imports 187Passing Data Among Methods 188Overloading Methods 191Creating Constructors 196Default Constructor 197Overloading Constructors 199Final Fields 202Order of Initialization 202Encapsulating Data 205Creating Immutable Classes 207Writing Simple Lambdas 208Lambda Example 209Lambda Syntax 211Predicates 214Summary 215Exam Essentials 216Review Questions 218Chapter 5 Class Design 233Introducing Class Inheritance 234Extending a Class 235Applying Class Access Modifiers 237Creating Java Objects 237Defining Constructors 238Calling Inherited Class Members 244Inheriting Methods 246Inheriting Variables 257Creating Abstract Classes 259Defining an Abstract Class 260Creating a Concrete Class 262Extending an Abstract Class 263Implementing Interfaces 266Defining an Interface 267Inheriting an Interface 269Interface Variables 273Default Interface Methods 274Static Interface Methods 278Understanding Polymorphism 279Object vs. Reference 281Casting Objects 282Virtual Methods 284Polymorphic Parameters 285Polymorphism and Method Overriding 287Summary 288Exam Essentials 289Review Questions 291Chapter 6 Exceptions 299Understanding Exceptions 300The Role of Exceptions 300Understanding Exception Types 302Throwing an Exception 304Using a try Statement 305Adding a finally Block 307Catching Various Types of Exceptions 309Throwing a Second Exception 311Recognizing Common Exception Types 313Runtime Exceptions 314Checked Exceptions 317Errors 317Calling Methods That Throw Exceptions 318Subclasses 319Printing an Exception 321Summary 323Exam Essentials 324Review Questions 325Appendix A Answers to Review Questions 333Chapter 1: Java Building Blocks 334Chapter 2: Operators and Statements 336Chapter 3: Core Java APIs 339Chapter 4: Methods and Encapsulation 342Chapter 5: Class Design 346Chapter 6: Exceptions 349Appendix B Study Tips 353Studying for the Test 354Creating a Study Plan 354Creating and Running Sample Applications 355Taking the Test 359Understanding the Question 359Applying Process of Elimination 362Optimizing Your Time 364Getting a Good Night’s Rest 366Index 367